KANSAS CITY, Mo. -- Kansas City firefighters were called to the scene of a hazardous material situation at the IRS building Friday.

According to James Garrett with the Kansas City Fire Department, about 10 people were in the mail room when a suspicious package showed up.

Since 10 a.m., FOX 4 has attempted to get more answers from the fire department, Homeland Security, Kansas City, Mo., police, the FBI, and the IRS, but no one has explained what happened.

FOX 4's Megan Dillard spoke to one IRS employee outside the building who said employees were sent an internal memo, although it didn't contain many details either. They were told the findings were 'inconclusive'. This internal memo reportedly said that 12 people were affected, with four going to the hospital and eight treated at the scene.

James Garrett, Kansas City, Mo., Fire Dept. told FOX 4's Megan Dillard that the fire department does not investigate suspicious packages and referred her to the IRS. Several phone calls to the IRS went unanswered.

A person on Facebook told FOX 4 that one person was sick to their stomach in the IRS building, and the vomitting caused others to be sick.

The 10 (now 12) people complained of chest pains, vomiting and sweating. You can watch that activity in the video player below.

Police are trying to figure out the best way to open the package to see what's inside. It has an odor of ammonia, but no powder or any other substance on the outside.

"We are inside the building," Garrett said. "We have the box isolated, so we have the box away from everybody else. It's in a room where it's isolated. We have that part of it done. We haven't gotten to exactly what the substance is yet."

Garrett says they have not ordered the IRS building to evacuate because the package has been quarantined. He believes emergency crews could be on the scene for one to three hours.

"It is a package," Garrett added. "It is airborne. We don't have reports of powder or anything like that, so whatever it was it was by smell and it was airborne."

Fox 4 will provide updates as they are confirmed.

Refresh this page for the latest.

Multiple first responders were on the scene of a suspicious package Friday morning.

Multiple first responders were on the scene of a suspicious package Friday morning.

Multiple first responders were on the scene of a suspicious package Friday morning.

Multiple first responders were on the scene of a suspicious package Friday morning.

Multiple first responders were on the scene of a suspicious package Friday morning.